Rivers: sharing, linking and disputes

Prelims and Mains

A quarter century of argument over the Sone has ended in a signature rather than in a tribunal. The Constitution offers States both routes, and which one they take decides how long the water stays unshared.

• Article 262 lets Parliament provide by law for deciding disputes over interstate river waters, and keep the courts out of them.
• The Inter-State River Water Disputes Act, 1956 is that law, under which the Centre constitutes a tribunal when a State asks for one.
• States may instead settle by negotiated agreement, which binds them without any tribunal at all.
• Bihar and Jharkhand signed a memorandum of understanding dividing the Sone's water, ending a dispute open since Jharkhand was carved out in 2000.
• Bihar takes 5.75 million acre-feet and Jharkhand 2, from the 7.75 undivided Bihar held under the Bansagar Agreement of 1973.
• The Sone rises near Amarkantak in Madhya Pradesh and joins the Ganga near Patna as a right bank tributary.

Prelims and Mains

The Home Minister has offered river linking as the answer that could keep India free of water shortage for a century. Every link is an inter-basin transfer, and the objection is that moving water to a basin in deficit creates a fresh claimant on water that already has users.

• The links are proposed under the National Perspective Plan of 1980 and worked up by the National Water Development Agency.
• A receiving region may demand its transferred water even in a distress year, at the cost of the original users.
• Tamil Nadu's requests for tribunals on the Pennaiyar in November 2019 and on Mekedatu in March 2026 are unanswered, one despite a Supreme Court direction.
• Demand side management is the alternative: conserve, reward efficient farm use, and curb groundwater drawn on free power.
• Ken-Betwa is the first link to be built, a 231 km canal carrying Ken water to the Betwa, with the Daudhan dam inside Panna Tiger Reserve.
• Ten villages will be submerged and twelve more displaced for compensatory afforestation.
• Adivasis in Chhatarpur allege eviction before compensation and irregular gram sabha consent.

Prelims and Mains

The Brahmaputra is the Yarlung Tsangpo in Tibet, so India and Bangladesh lie downstream of whatever China builds on it. There is no water treaty between the two countries, only a consultative channel for flood season data that China has closed before.

• The Expert Level Mechanism is the channel that data comes through, and it commits China to nothing.
• Construction began in July 2025 on a dam Chinese analysts project at about 60 GW, three times the Three Gorges.
• Water may be diverted through a 40 km tunnel at the Great Bend, so India cannot judge the effect downstream.
• India's ask is regular sharing and a joint impact assessment, not exchanges only during a disaster.
• More than 14,000 glacial lakes dot the Tibetan Plateau, growing fastest near China's southern borders.
• A flood from one can reach the border in minutes, so upstream data is part of a warning system rather than a courtesy.

Background reading: The Indian Express, 7 Sep 2026: Two countries and a shared river: Mistrust is not inevitable (opens in a new tab)

Prelims and Mains

On the Ganga, India is the upstream State and Bangladesh the downstream one, which is the relationship the Brahmaputra puts India on the other side of. The barrage at Farakka in West Bengal is where that position is exercised, by a structure built for a purpose inside India rather than for the border. Bihar, upstream of it, has a complaint of its own.

• The Farakka Barrage diverts Ganga water into the Bhagirathi–Hooghly to keep Kolkata port navigable.
• Bihar blames it for trapping silt upstream, a contested claim.
• The 1996 India–Bangladesh Ganga Water Sharing Treaty, which shares the lean season flow at Farakka, expires in December 2026.

Prelims and Mains

The Board was set up under the Brahmaputra Board Act, 1980 to prepare master plans for flood control, erosion and drainage, and remains advisory.

Prelims and Mains

The Chenab is a western river allotted to Pakistan, on which India may build only run of the river projects with little storage. India has held the treaty in abeyance since the Pahalgam attack, a step the treaty itself does not provide for.

Prelims and Mains

The Cauvery Water Management Authority implements the sharing of the river between Karnataka, Tamil Nadu, Kerala and Puducherry as fixed by the tribunal and modified by the Supreme Court in 2018, and Mekedatu is a dam Karnataka proposes on the river inside its own territory.

Prelims and Mains

The Mahanadi dispute between Chhattisgarh and Odisha went to a tribunal set up in 2018 under the Inter-State River Water Disputes Act, 1956, and the States may instead settle it by negotiation.